For loops in MATLAB - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the basic syntax of a for loop in MATLAB?

The basic syntax is:<br>

for index = startValue:endValue
    % code to repeat
end

<br>This repeats the code for each value of index from startValue to endValue.

beginner

How does a for loop in MATLAB differ from a while loop?

A for loop runs a fixed number of times, determined before the loop starts.

A while loop runs as long as a condition is true, which can change during execution.

intermediate

What happens if the loop variable in a MATLAB for loop is a vector?

The loop runs once for each element in the vector, assigning the loop variable to that element each time.<br>Example:<br>

for i = [2, 4, 6]
    disp(i)
end

prints 2, then 4, then 6.

intermediate

Can you modify the loop variable inside a MATLAB for loop? What happens?

Modifying the loop variable inside the loop does not affect the next iteration.<br>MATLAB sets the loop variable to the next value in the sequence at the start of each iteration regardless of changes inside the loop.

beginner

How do you exit a for loop early in MATLAB?

Use the break statement inside the loop.<br>When MATLAB encounters break, it stops the loop immediately and continues with the code after the loop.

What does this MATLAB code print?<br>

for i = 1:3
    disp(i)
end

A Error

B 3 2 1

C 1 1 1

D 1 2 3

The loop runs from 1 to 3, printing each number in order.

In MATLAB, what happens if you write:<br>

for i = [5 10 15]
    disp(i)
end

A It prints 5, then 10, then 15

B It prints 1 to 15

C It prints only 15

D It causes an error

The loop variable takes each value in the vector in order.

What is the purpose of the break statement in a MATLAB for loop?

A To skip the current iteration

B To stop the loop immediately

C To restart the loop

D To pause the loop

break stops the loop right away and continues after it.

If you change the loop variable inside a MATLAB for loop, what happens in the next iteration?

A The loop variable resets to the next value in the sequence

B The loop stops

C The changed value is used

D An error occurs

MATLAB resets the loop variable to the next value in the sequence regardless of changes.

Which of these is a valid for loop header in MATLAB?

A for i = 1 to 5

B for i in 1:5

C for i = 1:5

D for (i=1; i<=5; i++)

MATLAB uses for i = 1:5 syntax for loops.

Explain how a for loop works in MATLAB and give an example.

Think about how the loop variable changes each time.

Describe what happens if you modify the loop variable inside a MATLAB for loop.

Consider how MATLAB controls the loop variable each iteration.